The present invention relates to the production of a useful refractory material from the waste obtained from the manufacture and processing of aluminum and aluminum alloys commonly referred to as aluminum dross.
Aluminum dross contains significant quantities of aluminum as well as refractory material such as spinel, periclase, corundum and aluminum nitride. Unfortunately, the dross also contains significant quantities of salt such as halite and sylvite. It is these salts that create the problem in the reclamation of the dross.
One of the common techniques used in reclaiming the dross is the leaching or washing of the sodium and potassium salts out of the dross with water. A significant disadvantage of the leaching process is the creation of large volumes of brine solutions that must be disposed of with methods acceptable to environmental requirements.